Summary
Current industry practices for thermal rating of cables in unfilled troughs rely on conservative analytical methods outlined in IEC 60287 and CIGRE Technical Brochure 880, which often underestimate cable carrying capacity. While Finite Element Method (FEM) tools offer improved accuracy by modeling complete thermal environments, they present practical barriers: lack of standardization, requirement for specialized expertise, and inconsistency arising from nonlinear characteristics and user-dependent modeling decisions.
Read more Read lessThis study addresses the gap between overly conservative analytical methods and complex
FEM approaches by validating FEM-derived thermal rating techniques against real-world laboratory measurements. A full-scale 4-meter concrete trough with a trefoil cable bundle was first investigated applying continuous load. Results demonstrate excellent agreement between laboratory measurements and full multiphysics FEM predictions (maximum deviation 2.7%).
Furthermore, a semi-FEM approach that simplifies computational requirements while maintaining accuracy, was proposed, matching full FEM results within approximately 1%, whereas the standard IEC 60287 method produced errors up to 11.1%, significantly underestimating ampacity.
The findings conclude that proposed FEM framework provides superior accuracy for trough installations compared to existing analytical methods and justify their industry adoption. This research delivers both empirical validation and practical engineering tools to enhance thermal rating calculations.
Additional informations
| Publication type | Session Materials |
|---|---|
| Reference | B1_11868_2026 |
| Publication year | |
| Publisher | CIGRE |
| Country | Norway |
| Study committees | |
| File size | 2 MB |
| Price for non member | 30 € |
| Price for member | 30 € |
Authors
PORADOWSKI Wojciech - REN AS; ANDERS George J. - Łódź University of Technology; ENGEBRETHSEN Marius - REN AS; FJELD Elin - University of South-Eastern Norway
Keywords
KEYWORDS Current Rating Calculations, Empirical Correlation, Finite Element Method, Trough.
